Conventionally known in the art is a music playback apparatus to be used for listening to music while walking, which apparatus detects the walking rate (the tempo of the repetitive movement) of the user and alters the tempo of the music being played back to match the tempo of the repetitive movement so that the integrality of the user's movement and the music progression will be enhanced. An example of such a music playback apparatus is disclosed in unexamined Japanese patent publication No. 2003-85888.
Such an apparatus, however, synchronizes the music with the user's movement by simply altering the tempo of the same predetermined music piece. And accordingly, the music piece played back in a tempo which is different from its original tempo may sound unnatural and queer to the user as compared with its intended performance. Furthermore, mere change in tempo will not change the mood of the music, the user may get bored with the music and may lose the will to continue the exercise. In addition, in the case of a music piece recorded in a data format of tone waveform, the change in playback tempo will cause changes in tone pitch unless some special signal processing should be applied, and the user will feel a sense of strangeness.
Further known in the art is an automatic music playing apparatus which detects the heart rate of the user, calculates a exercise strength percentage from the detected heart rate, specifies tempo coefficients P=1.0 through 0.7 according to the calculated exercise strength percentage of from below 70% to above 100%, selects an automatic music playing data files (in the data format of musical notation) having the original tempo equal to the calculated tempo from among the stored music playing data files respectively prepared in various original tempos to correspond to various tempo coefficients as will be calculated. An example of such an automatic music playing apparatus is disclosed in unexamined Japanese patent publication No. H10-63264. The apparatus plays back a music piece having the original tempo which meets the exercise strength of the user. However, music playing data files only in the data format of musical notation (automatic performance data format) may present music having less rich musicality.
Still further known in the art is an exercise aiding apparatus which stores music piece data files of various tempos in the MIDI format (performance data format), calculates a walking rate to be informed of to the exerciser based on the characteristic information about the walking course and the physical conditions of the exerciser, presents to the exerciser a list of music numbers having a tempo which approximately coincides with the calculated walking rate from among the stored music piece data files, lets the exerciser select a desired music piece data file, modifies the tempo of the selected music piece data file to coincide with the calculated walking rate, and produces musical sounds of the modified musical data. An example of such an exercise aiding apparatus is disclosed in unexamined Japanese patent publication No. 2004-113552.
As all of such known apparatuses, however, uses music piece data files stored beforehand in the apparatus, increase in the total number of stored music data files would increase the capacity of the storage, while decrease in the total number may cause a situation that there is no music data file that satisfies the necessary conditions such as a tempo or that there are only a few such music piece data files so that the same music piece or pieces would be played back frequently and the user may get bored with the music. On the other hand, if the original tempo of a music piece should be changed to obtain a music piece data file of the required tempo, the played back music piece would sound unnatural.
Still further known in the art is a portable music player such as a MP3 (MPEG-1 Audio Layer-III) player which stores a multiplicity of music pieces and plays back music pieces in succession (one after another) automatically. However, such a player will not always play back music pieces to the user's liking. The played music piece may meet the user's taste some time, but the next (succeeding) number in the sequence may be of a different tempo or a different tonality.
Also known in the art is a music reproducing apparatus which evaluates the user's likes and dislikes about music pieces and adequately selects music pieces reflecting the evaluated liking, and automatically plays back the selected music pieces in succession. An example of such a music playback apparatus is disclosed in unexamined Japanese patent publication No. 2005-190640.
With the apparatus mentioned above, when the user pushes the skip button while a music piece is being played back, the apparatus quits the playback operation and evaluates the user's liking in value about the quit music piece reflecting the skip button operation, and registers the evaluation values in association with the music pieces to make a database of the user's liking about the music pieces. The publication discloses some examples of evaluation. For example, when the user manipulates the button to skip back (to cue) to the start of the music piece which was being played back heretofore, the heretofore registered evaluation value is increased by “+3.” It also discloses an “evaluation plus button,” an “evaluation minus button” and a “re-evaluation button.” It also discloses an idea of randomly selecting music pieces of the user's higher liking from among the stored music pieces based on the database about the user's liking information, but does not describe a specific embodiment therefor.
Generally speaking, in order to comply with various demands and likings about music pieces to be played back, the apparatus should store so many music piece data files, which will inevitably increase the capacity of the storage device. Further, this will need the work of storing so many music piece data files in the storage device beforehand, which work will be troublesome.
A way to dispense with such troublesome preparation may be to automatically compose music pieces instead of storing so many music pieces. However, conventionally known apparatuses and methods for composing music were to analyze and extract musical characteristic features of the existing music pieces and compose variety of music pieces. Such a trend can be seen in unexamined Japanese patent publication No. 2000-99015. So, there can hardly be found an apparatus or a method for automatically compose a multiplicity of music pieces which satisfy limited conditions such as a tempo of the music for creating music pieces.